Figure 1.

Study day timeline. Mean arterial pressure, heart rate, and middle cerebral artery blood velocity were continuously measured throughout the protocol. Participants completed two levels of difficulty of the Stroop color and word test. Each level consisted of a 2-min baseline period, a 3-min cognitive test, and a 2-min recovery period followed by a brief washout period. Participants then completed two levels of difficulty of the n-back working memory test following the same protocol. Indomethacin was administered followed by a 90-min wash-in period. Then, the cognitive testing protocol was repeated.